Thermostatic heat control



Aug. 12, 1930. F. PURDY THERMOSTATIC HEAT CONTROL Filed May 18, 1929 2 Sheets-Sheet l Z ZVEHKEF Jrederzlck Pu ref ll.

Aug. 12, 1930. F. PURDY 1,772,842

THERMOSTATIC HEAT CONTROL Filed May 18, 1929 2 Sheets-Sheet 2 fl tv m/z zyr: Grade rzlcli par dy.

Faterited Aug. 1% 1932 aaaaa FREDERICK PUBDY, 015 ram, MICHIGAN, ASSIGNOR T MVEL GA? OF FLINT, MICHIGAN, A COBPOTION OF ILLINOIS THERHOSTATIC AT CONTROL Application filed Kay 18, 1929. Serial 150. 864,061.

This invention relates to a heating control for the intake systems of internal combust on engines and has special reference to an 1mproved operating linkage for the heat control It is an object of this invent-ion to provide an improved valve operating linkage incorporating a thermostatic control adapted to shift the phase of the heat control element relative to the controlling element, which in the illustrated embodiment comprises the throttle valve of a carburetor. It has heretofore been proposed to alter the heat supply to a carbureter or manifold jacket in sue a way as to increase the heat supply for idling and to decrease or cut ofi' the heat supply for in order to provide maximum power at full throttle as it is a well known fact that while heatin a wet mixture increases the smooth- 29 ness 0 operation it also reduces the weight of the-charge entering an individual cylinder and thus reduces the power developed by a given cylinder volume. The present invention is directed towards shifting the phase relationship of the heat control mechanism in accordance with varying operating temperatures.

It is another object of this invention to pro-- vide an improved and simplified valve operating linkage embodying a thermostatic control that does not require complicated or special valve structures subjected to the fluids acted upon.

Other and further important objects of this invention will be apparent from the disclosures in the specification and the accompanying drawings.

This invention (in a preferred form) is illustrated in the drawings and hereinafter more fully described.

On the drawings:

Figure 1 is an'elevation of an engine manifolding system illustrating the application of one form of the device of this invention.

Figure 2 is a fragmentary detail with parts broken away to show the valves.

Figure 3 is a fragmentary view similar to Figure 2, showing another embodiment of this invention.

Figure 4 is a fragmentary side view of the link ofFigure 3.

On the drawings:

The manifold system of Figure 1 comprises a carburetor 10 having a throttle valve 11 on a shaft 12, the 'carbureter discharging into an intake manifold riser 13 jacketed as indicated by the reference numeral 14. The riser in turn opens into a horizontal distributing manifold 15 which is enveloped at the joint by a continuation 16 of the riser jacket 14,

this jacket 16 having twin ports 17 and 18.

opening into an exhaust manifold 19 on either side of an exhaust cut ofi valve 20 carried by a cross shaft 21. A partition 22 extends downwardly in the jackets 14 and 16 to guide the exhaust gases from the port 17 down one side of the riser, around the bottom of the partition and up the other side of the riser,

returning to the exhaust manifold through the port 18.

The present invention relates to means for operating the valve 20, in the exhaust manifold, in proportion to the movement of the throttle valve 11. The throttle shaft 12 carries a lever 23 and the exhaust valve shaft 21 is provided with a lever 24. in Figures 1 and 2 the lever 24 is provided with a slot 25 at an angle thereto so located as to follow the arc of movement of a connecting link 26. When.

the exhaust valve is in its extreme open position this relationship obviously does not hold as the valve is rotated clockwise in Figure 2 toward its open position parallel to the axis of the exhaust manifold as it will be evident that in such a position if the link is swung to the inner end of the slot it will result in increasing the opening of the valve.

The thermostatic control for varying the responsiveness of the exhaust valve to movement of the throttle valve comprises a volatile liquid container 27 formed as an expansible corrugated c linder one end of which is anchored by the ttin 28 and the other end is provided with a yo e 29 pinned to the link 26 at 30. As shown in Figure-2 in full lines the container 27 is partially expanded while the dotted lines indicate a collapsed position for a partial opening of the throttle In this figure the exhaust valve 20 is provided with a wide cooperating seat 31 in the manifold which has the effect of permitting a valve movement of approximately 15 before opening of tl:e main exhaust passage. This arrangement provides full exhaust gas diversion over a corresponding movement of the throttle valve and thus supplies more heat for operating conditions very closely approximating the slowest possible idling conditions.

The operation of the heat control, aside from the thermostatic features, ma be briefly summarized as a proportional ecrease in the diversion of exhaust gases through the riser jacket as the throttle is opened. The thermostatic control acts toincrease the opening of the exhaust valve and thus decreases the diversion of exhaust gases as the temerature of the thermostatic element rises ecause a rise of temperature expands the container 27 and shifts the upper end of the link 26 towards the inner end of the slot 25 thus increasing the opening movement of the exhaust valve.

The modification of F i ures 3 and 4 uses a plain lever 32 for the ex aust valve 20 and provides a two piece connecting link 33 and 34 separated by a cam 35 rotatable by a spiral bi-metal thermostatic strip 36 one end of which is anchored to the cam pivot 37 and the other end is pinned to the cam at 38 so that heating of the strip 36 causes uncurling thereof to rotate the cam counterclockwise, increasing the effective length of the link and thus shifting the exhaust valve towards its open position.

The two pieces of the link are held in alignment by a pilot 39 and are caused to follow the cam by a connecting spring 40.

In the operation of this form of the invention the base relationship of the two valves is altered by a change in the effective length of the connecting link while in the first form of the invention the relationship is changed by charging the effective lever arm of the exhaust valve lever.

It will thus be seen that I have provided an improved and simplified thermostatic heat control for varying the heating efiect in response to variations in operating temperatures.

I am aware that numerous details of construction may be varied through a wide range without departing from the principles of this invention, and I therefore do not pur ose limiting the patent ranted, otherwise t an necessitated by the prior art.

I claim as my invention:

1. In a heat control for internal combustion engines the combination with valves ar ranged to throttle the exhaust gases and intake charge, means for connecting said valves, and thermostatically responsive means associated with said connecting means and adapted to vary the ratio of movement of the exhaust controlling valve relative to the intake throttle valve.

2. In a heat control for internal combustion engines the combination with valves arranged to throttle the exhaust gases and intake charge, means for connecting said valves, and thermostatically responsive means adapted to vary the ratio of movement of the exhaust controlling valve relative to the intake throttle valve.

3. In combination with the exhaust and intake manifolds of an internal combustion engine, a control valve for said exhaust manifold, a bypass around said valve'formin a heating jacket for said intake manifolrfi a throttle valve in said intake manifold, linkage connecting said control and throttle valves, and thermostatic means for varying the ratio of movement of the control valverelative to the throttle valve.

4. In combination with the exhaust and intake manifolds of an internal combustion engine, a control valve for said exhaust manifold, a bypass around said valveforming a heating iacket for said intake manifold, a throttle valve in said intake manifold, linkage connecting said control and throttle valves, and thermostatic means acting on said linkage for varying the ratio of movement of the control valve relative to the throttle valve.

5. In combination with a variable heat control linked to the speed control of an internal combustion engine, of thermostatic means for varying the ratio between said heat control and said speed control.

6. In combination with a variable heat control linked to the speed control of an internal combustion engine, of thermostatic means for varying the effective length of the linkage between said heat control and said speed control.

In testimony whereof I have hereunto subscribed my name.

FREDERICK PURDY. 

